The Three Treasures of the Citrus: Antitumor Effects of Qingpi, Zhishi and Chenpi

Qingpi, Zhishi and Chenpi are the peel or fruit of unripe or ripe citrus or orange. The unripe citrus is green; its peel is collected for medicine and hence called Qingpi (green peel). The peel of the ripe citrus is yellow; the aged kind has a milder nature and is called Chenpi (aged peel) when used as medicine. If the unripe fruit of the orange is used as medicine, it is called Zhishi.

The Zhongyao Da Cidian (Great Dictionary of Chinese Materia Medica), under the entry "Qingpi," defines Qingpi as the tender or unripe fruit of the citrus plant (Rutaceae) and its cultivated varieties, cut into four pieces and the pulp within the segments removed before use; Zhishi is defined as the tender fruit of the sour orange and its cultivated varieties, or of the sweet orange.

Qingpi and Zhishi have very similar actions: both break qi and disperse accumulation, and resolve phlegm and relieve fullness.

The Zhongyao Da Cidian says Qingpi enters the liver, gallbladder and stomach channels; its main actions are to soothe the liver and break qi, and to disperse accumulation and stagnation. It treats pain and distension of the hypochondria, breasts and stomach, breast nodules, breast abscess, hernia, food accumulation, zheng-jia accumulations, and chronic-malaria masses. It has the effect of breaking up accumulated nodules and diaphragmatic qi.

Qingpi is often used in treating breast masses. Among the formulas for breast cancer recorded in Bencao Gangmu (Compendium of Materia Medica), there is one using only Qingpi alone: "For a nodule in the breast, as large as a finger, caused by long-standing melancholy, neither painful nor itchy, turning to an abscess after five or seven years, called breast cancer: take Qingpi four qian, in one and a half cups of water, decoct to one cup, and take slowly, one dose a day, or take it with wine." This formula is quoted from Zhu Danxi.

The "breast cancer" here is not necessarily what we call breast cancer today, but it may include breast cancer as well as hyperplastic breast diseases. It can be seen that physicians have used Qingpi against tumors since ancient times.

Moreover, Quansheng Zhimi Fang also records using Qingpi to treat "fuliang," which generally refers to digestive-tract tumors. The Fuliang Wan recorded there uses Qingpi (soaked in white-horse urine for three days until soft and thoroughly permeated, then sliced) thirty pieces, Badou (croton, skin removed) fifteen pieces (stir-fried together with Qingpi until dry; the Badou is then discarded and not used), and Qianghuo half a qian, ground together into powder and formed with white flour paste into pills as small as mung beans. Take five pills with water; if no effect, gradually increase to ten.

There are also records of Qingpi treating ascites. In Puji Fang, for a swollen, enlarged abdomen (i.e., today's ascites), one uses "Chenpi one liang, Badou ten pieces, Qingpi one liang, Gansui three qian. Stir-fry the herbs together, remove the Badou and Gansui, and use only the two peels as powder. Decoct Luobozi (radish seed), let it cool, and at bedtime take one qian-bi spoonful stirred in; around midnight also take half a qian-bi spoonful." In this formula the main use is Qingpi and Chenpi; Badou and Gansui are stir-fried but not used because these two are too toxic, so only their slight oily influence is taken and they must not be used in large doses. A qian-bi was an ancient measuring tool; one coin-measure is a very small amount, roughly one to three grams today.

From the above records we can see that using Qingpi to treat tumors or tumor complications has a long history. In treating tumor diseases I myself use Qingpi frequently. But the ancients also said Qingpi is strong in breaking qi and should be avoided in patients who sweat a lot, so when using Qingpi one should pay attention to its contraindications or pair it with qi-boosting herbs.

Zhishi enters the spleen, stomach and large-intestine channels; its main actions are to break qi and disperse accumulation, and resolve phlegm and relieve fullness. It treats internal stagnation, fullness and distending pain, constipation, tenesmus in diarrhea, binding chest, chest impediment, gastroptosis, uterine prolapse, and rectal prolapse.

The antitumor action of Zhishi has been confirmed by modern pharmacology. The naringin contained in Zhishi has a strong inhibitory effect in vitro on DNA synthesis in human cancer tissues (breast, colon, liver) but has no effect on normal human tissues (bone marrow, spleen, etc.). Naringin and naringenin can selectively inhibit cancer-cell growth, so Zhishi can be used to treat cancer patients resistant to chemotherapy and radiotherapy.

Yixue Qiyuan says of Zhishi: "The Zhizhu Miyao lists its four uses: first, it governs fullness below the heart (i.e., stomach distension); second, it transforms phlegm in the chest; third, it disperses undigested food and disperses stagnant blood; fourth, it breaks firm accumulations." The "breaking firm accumulations" mostly treats lump-type diseases.

In Jingui Yaolue (Synopsis of the Golden Chamber), Zhishi San treats postpartum abdominal pain with vexation and inability to sleep; it uses equal parts of Zhishi (burned until black, but not too much) and Baishao, pounded into a powder; take a fang-cun-bi spoonful, three times daily. Jingui Yaolue also emphasizes that this formula "also treats swellings and sores, taken down with wheat porridge." That is to say, Zhishi San can also disperse lumps in the body; it should be taken with wheat porridge, because Zhishi is strong in breaking qi and injures the stomach, and taking it with wheat porridge protects the patient's spleen and stomach.

Chenpi is the peel of the ripe fruit of the citrus plant (Rutaceae). The ancients preferred aged tangerine peel; the longer it is kept, the better the effect, hence the name Chenpi (aged peel). Long-aged Chenpi is much milder; it is no longer a qi-breaking herb but a qi-regulating, phlegm-resolving herb.

Chenpi enters the spleen, stomach and lung channels; its main actions are to regulate qi and harmonize the middle, downbear counterflow and stop vomiting, and dry dampness and resolve phlegm. It treats fullness in the chest and diaphragm, abdominal distending pain, poor appetite, vomiting, cough with much phlegm, and also the early stage of breast abscess.

Chenpi is one of the main herbs in Erchen Wan, the number-one TCM phlegm-resolving formula (Erchen Wan is so named because both its Chenpi and Fabanxia work better the more aged they are). Erchen Wan is very effective at resolving phlegm and stopping vomiting; I often advise patients undergoing chemotherapy to use Erchen Wan to counter the nausea and vomiting caused by chemotherapy, with good results.

Like the naringin in Zhishi, nobiletin (the active component of Chenpi) has also been confirmed to have a strong inhibitory effect on human cancer tissue. So Chenpi can also be used to treat cancer.

But in actual application, Qingpi, Zhishi and Chenpi have different emphases. In my own anti-cancer formulas I often use all three together, most often in equal amounts. But sometimes, according to the patient's clinical symptoms, I will heavily dose one particular herb.

Only, when using Qingpi, Zhishi and Chenpi in cancer patients, they must be used together with qi-boosting herbs such as Dangshen, Baizhu and Huangqi, otherwise they easily damage the patient's righteous qi.

Moreover, before using Qingpi, Chenpi and Zhishi, one should tell the patient in advance that these herbs may cause pain in the lesion area within minutes to two or three hours after taking the medicine. This prepares the patient mentally so that such a reaction will not alarm him.

Any qi-breaking, accumulation-dispersing herb—whether Qingpi, Chenpi or Zhishi, or Sanleng, Ezhu, Yujin, Jianghuang and so on—may cause pain in the lesion area, but if the patient persists for a while, he may be agreeably surprised to find the tumor shrinking.

To reduce the emotional disturbance such reactions cause, the physician may, when using the above herbs, appropriately pair them with pain-relieving herbs such as Yuanhu (Corydalis), to lessen the patient's bodily reaction.

Although the peel and tender fruit of the citrus all have such good anti-cancer effects, it is interesting that in the ancients' records, the citrus fruit itself was one of the foods that tumor patients should avoid.

Wang Hongxu, author of Waike Zhengzhi Quansheng Ji, said that tumor patients or skin-disease patients who eat citrus easily suffer a relapse. I myself live in a citrus-growing area; from childhood, both our own experience and the teaching of our elders told us that eating too many oranges easily gives boils, furuncles and swellings. So on my list of forbidden foods for cancer patients, I habitually put citrus among the foods that must be avoided.